chore: .scm -> .a2ml for 6a2 files (move to canonical location) + Justfile make->just

Per estate rule (user-confirmed 2026-04-30): .a2ml is canonical for 6a2
metadata files; .scm is reserved for Guix-related files only. The
six 6a2 metadata files were at repo root with .scm extensions; this
PR moves them to .machine_readable/6a2/<name>.a2ml as the canonical
RSR location. Content format (S-expression A2ML per
playbook-a2ml/spec) is unchanged; only the extension changes.

The pre-existing .machine_readable/6a2/STATE.a2ml was a 'secondary
short-form companion' per its own header. Its only unique content
(lifecycle on-enter/on-exit block) is appended to the new PLAYBOOK.a2ml
per the maintainer's parked-migration note in that file.

Separately: Justfile 'make build-tests' / 'make test-*' calls are
replaced with 'just <name>'. Makefiles are forbidden estate-wide and
no Makefile exists in this repo, so the make calls would silently
fail. Now they correctly invoke sibling Just recipes.

Out of scope (follow-up PRs):
  - Full RSR floor (~28 missing template files)
  - .md->.adoc conversion for non-githealth docs
  - Mandatory 4 RSR workflows (hypatia-scan, mirror, scorecard,
    rsr-antipattern per hypatia-rules @required_workflows)
  - Prose .scm references inside migrated content

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

AGENTIC.scm .machine_readable/6a2/AGENTIC.a2mlAGENTIC.scm renamed to .machine_readable/6a2/AGENTIC.a2ml

@@ -1,5 +1,5 @@
 ;;; ============================================================
-;;; AGENTIC.scm — gating rules for echo-types operational requests
+;;; AGENTIC.a2ml — gating rules for echo-types operational requests
 ;;; ============================================================
 ;;;
 ;;; Format: agentic-a2ml (S-expression, SRFI-30 conventions)

ECOSYSTEM.scm .machine_readable/6a2/ECOSYSTEM.a2mlECOSYSTEM.scm renamed to .machine_readable/6a2/ECOSYSTEM.a2ml

@@ -1,5 +1,5 @@
 ;;; ============================================================
-;;; ECOSYSTEM.scm — echo-types relationships across the
+;;; ECOSYSTEM.a2ml — echo-types relationships across the
 ;;; hyperpolymath repository constellation
 ;;; ============================================================
 ;;;

META.scm .machine_readable/6a2/META.a2mlMETA.scm renamed to .machine_readable/6a2/META.a2ml

@@ -1,5 +1,5 @@
 ;;; ============================================================
-;;; META.scm — echo-types architecture decisions from EI-2
+;;; META.a2ml — echo-types architecture decisions from EI-2
 ;;; ============================================================
 ;;;
 ;;; Format: meta-a2ml (S-expression, SRFI-30 conventions)

NEUROSYM.scm .machine_readable/6a2/NEUROSYM.a2mlNEUROSYM.scm renamed to .machine_readable/6a2/NEUROSYM.a2ml

@@ -1,5 +1,5 @@
 ;;; ============================================================
-;;; NEUROSYM.scm — formal-evidence semantics for EI-2 termination
+;;; NEUROSYM.a2ml — formal-evidence semantics for EI-2 termination
 ;;; ============================================================
 ;;;
 ;;; Format: neurosym-a2ml (S-expression, SRFI-30 conventions)

PLAYBOOK.scm .machine_readable/6a2/PLAYBOOK.a2mlPLAYBOOK.scm renamed to .machine_readable/6a2/PLAYBOOK.a2ml

@@ -1,5 +1,5 @@
 ;;; ============================================================
-;;; PLAYBOOK.scm — operational procedures for echo-types sessions
+;;; PLAYBOOK.a2ml — operational procedures for echo-types sessions
 ;;; ============================================================
 ;;;
 ;;; Format: playbook-a2ml (S-expression, SRFI-30 conventions)
@@ -265,6 +265,26 @@
      (role . "If a 6a2 schema question arises that this PLAYBOOK doesn't resolve.")
      (hours . "asynchronous"))))
 
+;;; ============================================================
+;;; Session lifecycle (migrated from former .machine_readable/6a2/STATE.a2ml
+;;; "secondary short-form companion" file as part of the 2026-04-30
+;;; .scm -> .a2ml migration. The original file's own header marked this
+;;; block as the only unique contribution it carried.)
+;;; ============================================================
+
+(define lifecycle
+  '((on-enter
+     (step . "Read .machine_readable/6a2/STATE.a2ml first")
+     (step . "Read .machine_readable/6a2/META.a2ml for permanent decisions")
+     (step . "Check status.phase before starting any work")
+     (step . "If user asks about EI-2: state TERMINATED; refer to ei-2 block in STATE"))
+    (on-exit
+     (step . "Update status.phase if changed")
+     (step . "Update commits-pushed if any commits actually pushed")
+     (step . "If new questions opened, add to open-questions block in STATE")
+     (step . "If naming-traps encountered, add to naming-traps block in STATE")
+     (step . "Never remove the ei-2 block; it is permanent record"))))
+
 ;;; ============================================================
 ;;; END OF PLAYBOOK
 ;;; ============================================================

.machine_readable/6a2/STATE.a2ml

@@ -20,7 +20,7 @@ build-all:
 	@echo "🔨 Building all echo type modules and tests..."
 	@echo "=========================================="
 	just build-echo
-	make build-tests
+	just build-tests
 	@echo "=========================================="
 	@echo "✅ Build complete! All modules type-check successfully"
 
@@ -57,11 +57,11 @@ test-stability:
 test-all:
 	@echo "🧪 Running comprehensive test suite..."
 	@echo "=========================================="
-	make test-core
-	make test-cno
-	make test-thermo
-	make test-cat
-	make test-stability
+	just test-core
+	just test-cno
+	just test-thermo
+	just test-cat
+	just test-stability
 	@echo "=========================================="
 	@echo "✅ All tests passed! Stability: 92/100"
 
@@ -75,9 +75,9 @@ clean:
 verify:
 	@echo "🔬 Full verification cycle..."
 	@echo "=========================================="
-	make clean
-	make build-all
-	make test-all
+	just clean
+	just build-all
+	just test-all
 	@echo "=========================================="
 	@echo "✅ Verification complete! System stability: 92/100"
 
@@ -103,5 +103,4 @@ stability-report:
 
 # Default target
 default:
-	make verify
-
+	just verify